I’m looking at a M1892 rifle, 1905 production, octagon barrel, 32-20.   I have 3 questions :

1)  The rear site elevator is missing.   Would the original have been an elevator with the thumbpiece or without?

2)  One of the tang screws is MIA.  It is hard for me to come up with a scenario in which a screw the size of a tang screw would simply loosen up and fall out.  To me, a more likely scenario is that the gun was disassembled and it was lost.   Any thoughts?

3)  Where can I find original replacement parts for the above?

Thank you,

War Eagle